Most of the immunochemical and physical analyses of porcine C5a anaphylatoxin have been completed. However, we have been unable to demonstrate carbohydrate in the porcine C5a in contrast to the large content of carbohydrate demonstrated in the human counterpart. Part of our effort will be directed to elucidate the existence of such species differences, using a different methodology for the isolation of porcine C5a AT. At the same time, the effect of anaphylatoxin potentiating substances will be explored. In preliminary experiments compounds with bradykinin potentiating activity have also been shown to have an anaphylatoxin potentiating effect. Specifically, epsilon amino caproic acid and peptides which have been isolated from the serum of Bothrops jararaca. These studies will further aid to the understanding of the biological function of anaphylatoxins and the possible structural differences of the C5a AT from different species. BIBLIOGRAPHIC REFERENCES: Vallota, E.H.: Inhibition of C5 convertase by Epsilon Amino caproic acid: A limiting factor in the generation of C5a anaphylatoxin. Abst. Fed. Proc. 36, 1245, 1977 (manuscript in preparation). Forristal, J., K. Iitaka, E.H. Vallota and C.D. West: Correlation between serum factor B and C3b inactivator levels in normal subjects and in patients with infections, nephrosis and hypocomplementemic glomerulonephritis. Clin. Exp. Immunol. 1977 (accepted for publication).